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Authors requiring further information regarding Elsevier’s archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright Author's personal copy Gondwana Research 23 (2013) 354–366 Contents lists available at SciVerse ScienceDirect Gondwana Research journal homepage: www.elsevier.com/locate/gr A new Ordovician eurypterid (Arthropoda: Chelicerata) from southeast Turkey: Evidence for a cryptic Ordovician record of Eurypterida James C. Lamsdell a,⁎, İzzet Hoşgör b, Paul A. Selden a,c,d a Paleontological Institute and Department of Geology, University of Kansas, Lawrence, Kansas, United States b TransAtlantic Petroleum Ltd.-Viking Int. Ltd. TR-06680, Ankara, Turkey c Natural History Museum, London, United Kingdom d Capital Normal University, Beijing, PR China article info abstract Article history: A new species of eurypterid, Paraeurypterus anatoliensis gen. et sp. nov., is described from the Upper Received 27 January 2012 Ordovician (Katian) Şort Tepe Formation of southeast Turkey. The single specimen, preserving the carapace, Received in revised form 20 April 2012 mesosoma and fragments of appendages, appears morphologically intermediate between the eurypteroid Accepted 20 April 2012 families Dolichopteridae and Eurypteridae. P. anatoliensis retains the plesiomorphic conditions of crescentic Available online 2 May 2012 eyes with enlarged palpebral lobes and a quadrate carapace with ornamentation consisting of small pustules Handling Editor: J.G. Meert but also displaying the derived characteristics of genal facets and a row of large acicular scales across the posterior of each tergite. Phylogenetic analysis incorporating each of the major eurypterine clades and Keywords: all Eurypterina having a three-segmented genital operculum (the triploperculate condition) resolves Katian eurypteroids to be an unnatural group, with Dolichopteridae and Eurypteridae forming part of a grade Eurypterina leading to diploperculate Eurypterina. P. anatoliensis is intermediate between the two eurypteroid families, Paraeurypterus as is ‘Eurypterus’ minor from the Pentland Hills of Scotland, which is shown to be a distinct genus and Ghost ranges assigned to Pentlandopterus gen. nov. Using the phylogenetic topology to infer ghost ranges for each of the Phylogeny major eurypterid clades reveals that the majority of eurypterid superfamilies must have originated by the Katian, indicating a largely unsampled record of Ordovician eurypterids. The occurrence of poor dispersers such as Paraeurypterus in the Ordovician of Gondwana is puzzling, and it has been suggested that they dispersed to the continent during periods of sea level lowstand in the Sandbian and Hirnantian, however this does not explain the lack of Ordovician species in North America and Europe, given the well-sampled nature of these continents, and an alternative is proposed whereby eurypterids originated in Gondwana and radiated out to Laurentia and Baltica in the late Ordovician and early Silurian, thus explaining their sudden appearance in the European and North American rock record. Published by Elsevier B.V. on behalf of International Association for Gondwana Research. 1. Introduction held view that the observed distributions represent a true signal, with eurypterids originating in Laurentia and being limited to dispersal Eurypterids are a monophyletic group of Palaeozoic aquatic along coastlines, with only the pterygotoids being able to cross open chelicerates with a distribution largely limited to the palaeo- oceans (Tetlie, 2007a). Any new record of eurypterids from outside continents of Avalonia, Armorica, Baltica, Iberia and Laurentia. Of North America and Europe is, therefore, of extreme interest, the 246 currently valid eurypterid species only 22 have been reported especially if they can be assigned to a group lacking the dispersal from outside these palaeocontinents; however, of these, only 13 can capabilities of the pterygotoids, and have a pre-Carboniferous age. be confidently assigned to a eurypterid clade (Table 1). While it has The majority of eurypterid occurrences outside North America and been suggested that the lack of eurypterids other than from Europe Europe consist of presumably poor dispersers (hibbertopteroids) and North America is a collecting and research bias (Plotnick, 1999), which occurred during the Carboniferous and Permian, after and a number of further unnamed or fragmentary eurypterids have Gondwana has come into close proximity to Laurentia as a prelude been reported from outside of these continents (Braddy et al., 1995, to the amalgamation of Pangaea, or taxa with higher dispersal 2002; Braddy and Almond, 1999; Tetlie et al., 2004), it is the currently potential such as pterygotoids or carcinosomatids. Adelophthalmus Jordan in Jordan and von Meyer, 1854, another widespread genus, is ⁎ Corresponding author. also known from Gondwanan localities from the Devonian onwards E-mail address: [email protected] (J.C. Lamsdell). and it is likely that it was able to cross the already narrowing gulf 1342-937X/$ – see front matter. Published by Elsevier B.V. on behalf of International Association for Gondwana Research. doi:10.1016/j.gr.2012.04.006 Author's personal copy J.C. Lamsdell et al. / Gondwana Research 23 (2013) 354–366 355 Table 1 Chronological list of undoubted eurypterids from palaeocontinents other than Baltica, Laurentia, Avalonia, Iberia and Armorica. Stylonurus (?) menneri and Borchgrevinkium taimyrensis from the early Devonian of Siberia (Novojilov, 1959) and Melbournopterus crossotus from the Silurian of Australia (Caster and Kjellesvig-Waering, 1953) are not eurypterids and so have not been included. Eurypterus loi, Eurypterus styliformis and Eurypterus yangi from the Silurian of China (Chang, 1957) are probably based on undiagnostic material and have been excluded pending reevalution of the original material, as have Nanahughmilleria schiraensis and Parahughmilleria matarakensis from the Devonian of Siberia (Pirozhnikov, 1957), Adelophthalmus carbonarius (Chernyshev, 1933) from the Carboniferous of Ukraine, and Pterygotus (?) australis from the Silurian of Australia (McCoy, 1899). Note however that reports of unnamed or undescribed eurypterids (Braddy et al., 1995, 2002; Braddy and Almond, 1999; Tetlie et al., 2004) are not listed here. Eurypterids by period Author Age Region Ordovician Onychopterella augusti Braddy et al., 1995 Hirnantian South Africa Silurian Hughmilleria wangi Tetlie et al., 2007a Llandovery China Rhinocarcinosoma dosonensis Braddy et al., 2002 Ludlow–Pridoli Vietnam Slimonia boliviana Kjellesvig-Waering, 1973 Ludlow/Pridoli Bolivia Devonian Acutiramus cf. bohemicus Burrow et al., 2002 Pridoli Australia Adelophthalmus waterstoni Tetlie et al., 2004 Frasnian Australia Pterygotus bolivianus Kjellesvig-Waering, 1964a Emsian/Eifelian Bolivia Carboniferous Adelophthalmus irinae Shpinev, 2006 Tournaisian Siberia Cyrtoctenus wittebergensis Waterston et al., 1985 Tournaisian South Africa Megarachne servinei Hünicken, 1980 Gzhelian–Asselian Argentina Unionopterus anastasiae Chernyshev, 1948 Tournaisian–Visean Kazakhstan Permian Adelophthalmus chinensis Grabau, 1920 Asselian China Campylocephalus oculatus Kutorga, 1838 Guadalupian? Russia Hastimima whitei White, 1908 Sakmarian Brazil between Gondwana and Laurentia. One occurrence, however, appears unnamed, thick, Cambrian limestones overlain by approximately to defy explanation: Onychopterella augusti Braddy et al., 1995, from 1000 m of the Giri Formation, comprising Silurian (actually Cambrian the Soom Shale of South Africa, which has been dated as latest and Ordovician) quartzites with subsidiary limestones and siltstones. Hirnantian to earliest Rhuddanian (Vandenbroucke et al., 2009). Some of the latter contained Cruziana trace fossils and have been O. augusti does not appear to be a good disperser, as its posterior compared to analogous strata in northern Iraq (Dean and Monod, pair of appendages are not overly expanded into a swimming paddle, 1990; Dean, 2006). Between Hakkari and Çukurca the River Zap cuts a and its relatively basal phylogenetic position combined with its early deep valley to expose two inliers of Cambrian and Ordovician sediments, occurrence (before the major period of eurypterid radiation during mostly clastics, that form part of the Arabian Platform (Ghienne et al., the early Silurian) makes its appearance in Gondwana somewhat 2010). Dean et al. (1981) recognised that the Giri Formation was problematic. equivalent to the shales and sandstones of the Seydişehir Formation, Here, we report a second Gondwanan Ordovician eurypterid, described from the western Taurus Mountains but widespread in the Paraeurypterus anatoliensis gen. et sp. nov., a single specimen eastern Taurus, southeastern Turkey, and neighbouring parts of Iraq, from the Şort Tepe Formation (middle Katian) near Çukurca, and of Upper Cambrian and Lower Ordovician age. The strata southeast Turkey. The new species is placed